1. Field of the Invention
The present invention relates to a reed valve used primarily for a check valve of diaphragm-type pump, and particularly to a reed valve for a pump in which the structure of the reed valve is improved to have good sealability and increased discharge pressure.
2. Description of Background Information
In a diaphragm-type pump, the amount of fluid discharged per unit discharge operation is generally small, about 0.5 cc. Therefore, when a self-suction force, such as a suction force of fluids under the condition where the pump is not primed and a discharge force (discharge pressure) needs to be generated, the sealability of a portion of check valve becomes important to pumping. However, conventional reed valves used for diaphragm-type pumps have disadvantages in that the sealability thereof is insufficient and thus the discharge pressure and discharge quantity are low, resulting in poor pump performance.
Thus, heretofore, in order to increase the sealability of a reed valve, umbrella-type check valves made of pliable material such as rubber were arranged on the suction port and the discharge port outside the reed valves. However, when a polar solvent such as ketone is one of the fluids to be carried by the pump, a rubber valve is apt to deteriorate, so that fluids to be carried by pumps having such valves are limited to only certain fluids. On the other hand, it is difficult to form an umbrella-type valve of material having chemical resistance.